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Dr. Fauci explains why coronavirus vaccines come in two doses

Dr. Fauci explains why coronavirus vaccines come in two doses
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Whenever you get vaccinated for the coronavirus, there is a good chance you will need to get two doses of the vaccine. Two types of vaccines are expected to begin being distributed this month and both require two doses 28 days apart.

Dr. Anthony Fauci said during a CNN town hall on Friday that the first vaccine is the “prime” vaccine dose, and the second one is a booster. The two vaccines, one from Pfizer and the other Moderna, are expected to receive an FDA emergency use authorization in the coming weeks.

Fauci said another vaccine, one produced by Johnson and Johnson, would only require one shot. But Fauci cautioned that the data from that vaccine candidate has not been reviewed. The Moderna and Pfizer vaccines are showing an efficacy of 95%, and both vaccines had a near 100% effectiveness against severe coronavirus cases.

While the first shot will offer some protection against the virus, Fauci says that the boost will give Americans “optimal” protection against the virus.

“What you have is you get some degree, not optimal, but some degree of immunity a couple of weeks after the first dose,” Fauci said. “That's not optimal. After the second dose, you get optimal immunity anywhere from seven to 10 days after the second dose."

As vaccine doses begin to make their way to health care workers and high risk patients, Fauci says it will be important for everyone, even those who are vaccinated, to still wear masks and conduct social distancing. Fauci says that those who are vaccinated could potentially carry the virus, even if they will not become symptomatic.

Fauci said that it will take a vast majority of Americans getting vaccinated before the US reaches herd immunity. When the US reaches herd immunity, that is when social distancing measures can be eased, Fauci says.

"Even if you're vaccinated, you may be protected against getting sick, but you may not necessarily be protected against getting infections. So you may have some virus in your nasal pharynx. It wouldn't bother you, and maybe it wouldn't even infect anybody else, but it would be there. That's the reason why you can't abandon all public health measures."